Gately DynaQuad ENCODER - info appreciated

[afalout]

Hello all,

I have recently acquired Gately encoder, see attached photos. It looks like a reasonably simple thing, but it's behaving quite strangely. So I'm wondering if anyone here had seen one before or perhaps has one, possibly any kind of ?

Any info much appreciated.

PS. I'm looking for a HARDWARE QS and EV4 encoders if anyone has one to sell...

Andrej

 

[furui_suterioo]

That diamond/square layout mode switch is interesting, I'm not sure how accurately diamond layout will be decoded if you are using QS to monitor the output. I have the Dynaco Quadapter but haven't tried it yet(not sure if its compatible with my amp), the Involve encoder(Involve Encoder evaluation kit – INVOLVE AUDIO) is compatible with QS.

 

[Sonik Wiz]

Hello all,

I have recently acquired Gately encoder, see attached photos. It looks like a reasonably simple thing, but it's behaving quite strangely. So I'm wondering if anyone here had seen one before or perhaps has one, possibly any kind of ?

Any info much appreciated.

PS. I'm looking for a HARDWARE QS and EV4 encoders if anyone has one to sell...

Andrej

Hey Anrej
Interestingly the Gately Encoder was briefly talked about a while back. Check out:
A Sunday with Involve

Staring at post 58.

Some what along the lines of what Furui said, when you say it's behaving quite strangely it begs to question how are you testing and evaluating it? Are you feeding test tones & measuring the encoded output? Are you using discrete 4ch audio as a source & evaluating through a decoder? If so what kind of decoder?

 

[J. PUPSTER]

That diamond/square layout mode switch is interesting, I'm not sure how accurately diamond layout will be decoded if you are using QS to monitor the output. I have the Dynaco Quadapter but haven't tried it yet(not sure if its compatible with my amp), the Involve encoder(Involve Encoder evaluation kit – INVOLVE AUDIO) is compatible with QS.

what's your new avatar there f_s?

 

[furui_suterioo]

what's your new avatar there f_s?

It's a manipulation of this photo of a CD-4, with Japan quad badge over:

View attachment 49837

I had been contemplating a new avatar for some time, I figure now is the opportunity

 

[Sonik Wiz]

It's a manipulation of this photo of a CD-4, with Japan quad badge over:

I had been contemplating a new avatar for some time, I figure now is the opportunity

You haven't lost the love for Kenwoods, have ya?

 

[furui_suterioo]

You haven't lost the love for Kenwoods, have ya?

Nope! They would could still get away with murder

 

[par4ken]

Not a lot to a Dyna encoder. looks like It uses one of the earliest op-amp types the 709. Sorry that I can't be of more help, not sure what you mean by it's behaving strangely. Not a lot to go wrong in a simple unit like that. If it was mine I'd replace all the capacitors and use better op-amps, unless you want to retain it's vintage sound quality.

 

[Sonik Wiz]

Not a lot to a Dyna encoder. looks like It uses one of the earliest op-amp types the 709. Sorry that I can't be of more help, not sure what you mean by it's behaving strangely. Not a lot to go wrong in a simple unit like that. If it was mine I'd replace all the capacitors and use better op-amps, unless you want to retain it's vintage sound quality.

Wasn't the 709 an equiv of the 741 op amp? Also one of the earliest that helped give audio op amps such a bad rep.

At one time I had an EV 4 encoder. 19" rack mount, 4 big meters which was pretty cool. But almost nothing inside. So easy to do the same & better today, if you want

 

[par4ken]

Wasn't the 709 an equiv of the 741 op amp? Also one of the earliest that helped give audio op amps such a bad rep.

At one time I had an EV 4 encoder. 19" rack mount, 4 big meters which was pretty cool. But almost nothing inside. So easy to do the same & better today, if you want

The 709 came before the 741, it had no internal frequency compensation. An EV encoder would be just as simple as the Dyna.

 

[afalout]

Thanks for your input, everyone.

I allready re-capped the PSU, no other elcos in it. I got this for authenticity and historic value (it would probably be the first commercally available Quad encoder?), and allready have CBS SQ encoder, so two more to go (Well 4, if we count Denon, but I dont think thir matrix encoders where commercially available, and I think same goes for RM encoders in all disguises - sans Sans-sui - if you want to call it RM)

So would prefer to keep the op-amps - if I can get them working. Easy enough to try it with better op-amps later, as it has a plug-in base for op-amps. What would you guys recommend as a pin-compatible direct replacement?

When I say behaving strangely, when I connect the inputs, the moment when ground on input gets in contact, the unit starts oscillating on output (about 5khz). Loudly. My best guess is that the output XLRs are not wired in a (what we would call in 2020) standard way, and that the unit essentially short-circuits on inputs.

This is a non-balanced (single-ended) model variant without output transformers, so I'm using the XLR-RCA adapters (that of course have minus pin bridged to the ground)

@Sonik Wiz - do you still have that EV4 encoder, I am looking for one?

BTW - one of the articles I found on this unit, mentiones that it is actually both a DynaQuad and EV-4 encoder - is this possible? The "diamond" / square switch I thought is just for the Dynaco Diamond original layout vs the later square one... (I dont have any manuals whatsoever)

Thanks,
Andrej

 

[par4ken]

IMHO The TL071 is as good as anything for general audio use. The 709 in that encoder has is a 14-pin DIP, 8-pin DIP's are much more common and will fit in the same socket if you line the pins up correctly. Check the data sheet. https://www.ee.nsysu.edu.tw/lab/F6027/LM709 Operational Amplifiers.pdf Most 8-pin op-amps share the same pin-out. I don't think that the compensation capacitor would make a difference as those pins are unused on a compensated op-amp, or the capacitor can be removed. As part of a collection of vintage encoders I would just leave as is. The XLR adaptors might be causing the problem. The negative input is connected to ground in those. There was more than one standard for the pin connections on those. Connector Pinout Drawings - Clark Wire & Cable Try to disconnect the negative pin from ground in the adaptor.

 

[Sonik Wiz]

do you still have that EV4 encoder, I am looking for one?

Sorry, no. That was a lone from an old time Quaddie named Dave Winner waaaay back in late 70's. I had it for a while to evaluate for purchase but I also had a Sansui QSE-5B encoder that was more useful to me. Yes, nice meters tho.

Please keep us informed how your Gately project goes! And will you use it for any practical quad purposes or just collecting?

 

[MidiMagic]

The Gately Encoding equations are as follows:

Diamond:

Lt = L + .707 F + .707 B
Rt = R + .707 F - .707 B

Square:

Lt = LF + .25 RF + LB - .5 RB
Rt = RF + .25 LF + RB - .5 LB

EV (for comparison)

Lt = LF + .3 RF + LB - .5 RB
Rt = RF + .3 LF + RB - .5 LB

A 2-pole switch and 2 resistors could be used to change the Gately square encode to EV encode.

 

[afalout]

Please keep us informed how your Gately project goes! And will you use it for any practical quad purposes or just collecting?

Will do. I am working on assembling (what I consider to be) the ultimate Quad system, so having encoders is helping me measure and evaluate decoders - bypassing the distribution media limitations. There is also a shortage of (technical) test records for most formats excluding SQ, so this way I can verify my decoders are operating within specs using proper signal generators and can use multi-channel scopes to directly compare inputs with outputs in 4:2:4 topology.

Incidentally - I failed so far to locate an "active" (line-level) decoder for Dynaco Diamond/Dynaquad - Im only aware of the Quadaptor (speaker-level) and few amps with the same built-in. Does anyone know of some such? My amps would fry the Quadaptor in 30 seconds flat ...

PS For future reference I am attacking a two pics of the vesion of Gately with ballanced output transformers.

 

[afalout]

The Gately Encoding equations are as follows:

...

A 2-pole switch and 2 resistors could be used to change the Gately square encode to EV encode.

Thanks for the info - I will be tempted to try this if I fail to find original EV4 encoder in foreseeable future.

How would I know where to add resistors & switch?

PS. Again a big THANK YOU for your web site, MidiMagic. It helped me enormously.

 

[afalout]

Also - can you guys help me, what is the best way to advertise a "wanting to buy" here for original EV4, QS and UHJ encoders? (Analog-only of course). Also have a few other bits on my want list...

Cheers

 

[furui_suterioo]

Attached is a page about Gately/Dynaco came across when searching EV encoder, it doesn't say on the page but the name of the EV encoder for $795 is the Electro-Voice Model 7445, which I assume is what Sonik had.

 

[Soundfield]

Attached is a page about Gately/Dynaco came across when searching EV encoder, it doesn't say on the page but the name of the EV encoder for $795 is the Electro-Voice Model 7445, which I assume is what Sonik had.

The sad thing about that article is that it highlights how much has been dumbed down over the last thirty or forty years. No HiFi mag these days (not that there really are any) would run a technical article like that for fear of its readers’ fleeting attention span or understanding of rudimentary maths. Back in the seventies, HiFi News & RR review would happily run a ten or twenty page technical or engineering piece. And they were full pages of closely typed text, not a couple of paragraphs smeared across pages taken up largely by glossy photographs and adverts! So much for progress!

 

[afalout]

The sad thing about that article is that it highlights how much has been dumbed down over the last thirty or forty years.

Sadly, it seems this holds true for many other aspects of life in general. Some depth is retained in places like this, and few other channels (dare I mention Youtube?) but in a bottom-up structure, so too often it is all about blind leading the blind... Who is going to build the nirvana of AI and robots when this generation is gone? I am already afraid that no more then few dozen people on the planet would know how to build a present day TV....